Upgrade windows 7 to windows 8

Question

Windows

I understand that the question looks very strange but nevertheless.
I have a windows 7 home basic key from which is written on the back cover of the laptop,
when windows 8 came out I bought an upgrade for 500 rubles, they gave me a new key and a master to upgrade to windows 8, I entered this new key there and everything was fine with me .
It so happened that I completely broke my windows 8, and wanted to reinstall it.
I downloaded the version of windows 8.1 tried to put it by entering the key that I received earlier - it says the wrong key.
I then found a disk with windows 7 installed it and decided to upgrade to 8 using the same key.
I found an instruction , but there they offer me to buy a new win8 again and nowhere is there such an option that I already have an upgrade key:

How to do it right, provided that you don’t want to buy win 8 again?

Answer 1

When installing 8.1, use the engineering keys from here . These keys allow you to install Windows 8.1 but not activate it.
Next (installation field) activate the key to your upgrade.
Important - select the key correctly - Pro or Core (Core is which is not Pro)
These keys definitely help to get around the problem "Windows 8.1 is not installed with a key from Windows 8.0". We put it with engineering keys, then we change the key to Windows 8 and activate it.
(IMPORTANT) This does not work for Enterprise. Enterprise 8.0, in principle, "does not upgrade" to 8.1 by-Design. In the case of Enterprise, these are two completely different OSes and for them the same rules for upgrading 8.0 to 8.1 as for upgrading XP to 7.0 or 7.0 to 8.0

Answer 2

The plans are to reinstall the system, the situation is exactly the same (with the exception of the pro edition).
From what I found:
habrahabr.ru/post/202268
habrahabr.ru/post/203434
If it helps or you find your own solution, it would be nice to see the answer.